Indicators covalently bound to insoluble carriers

• US 3,904,373 A
• Filed: 10/26/1973
• Issued: 09/09/1975
• Est. Priority Date: 10/26/1973
• Status: Expired due to Term

• Current Assignee: Gerald Bruce Harper
• Original Assignee: Gerald Bruce Harper
• Inventors: Harper, Gerald Bruce
• Primary Examiner(s): Padgett, Benjamin R.
• Assistant Examiner(s): Gron, T. S.
• Application Number:
  US05/409,876
• Time in Patent Office: 683 Days
• Field of Search: 252/408 23/253TP 424/7
• US Class Current: 422/425
• CPC Class Codes: G01N 31/22 using chemical indicators G01N31/02 takes precedence
• CPC Class Codes: G01N 31/221 for investigating pH value

Abstract

Indicators insolubilized by covalent bonding to inorganic carriers for indicating the hydrogen ion concentration, oxidation-reduction state or specific ion concentration in liquid media. Since the indicators are insoluble they do not contaminate the solution tested, and they may be used repeatedly in different media. They replace the well known indicator test papers which consists of a substrate dyed with an indicator. Methods of making the indicators are also provided.

Claims

1. AN INSOLUBILIZED BOUND INDICATOR USEFUL IN DETERMINING PARAMETERS SUCH AS HYDROGEN ION CONCENTRATION (PH), OXIDATION-REDUCTION POTENTIAL OR SPECIFIC ION CONCENTRATION IN SOLUTIONS CONSISTING OF AN ORGANIC INDICATOR COVALENTLY COUPLED BY MEANS OF AN ORGANO-FUNCTIONAL SILANE COUPLING AGENT TO AN INORGANIC CARRIER HAVING AVAILABLE HYDROXYL OR OXIDE GROUPE GROUP

2. A bound indicator as claimed in claim 1 wherein said silane coupling agent is combined with said indicator by means of an alkyl linkage.

3. A bound indicator as claimed in claim 1 wherein said silane coupling agent is combined with said indicator by means of an azo linkage.

4. A bound indicator as claimed in claim 1 wherein said silane coupling agent is combined with said indicator by means of a sulfonamide linkage.

5. A bound indicator as claimed in claim 1 wherein said silane coupling agent is represented by the general formula XnSiR(4 n) in which X represents a substituted or unsubstituted aryl, alkyl or alkyl-aryl group, the substituent(s) being selected from groups which include hydroxy, lower alkoxy, amino, lower alkylamino, lower dialkylamino, alkyl, nitro, nitroso, diazo, cyano, isocyano, isothiocyano, carboxy, carbonyl, keto, halocarbonyl, sulfoxy and halosulfonyl;

R represents a group which may be lower alkoxy, aryloxy or halogen; and

n is one of the integers, 1, 2 and 3.

6. A bound indicator as claimed in claim 1 wherein said carrier is a glass.

7. A bound indicator as claimed in claim 1 wherein said carrier is zirconia coated glass.

8. A bound indicator as claimed in claim 1 wherein said carrier is a metal oxide.

9. A bound indicator as claimed in claim 1 wherein said carrier is nickel oxide.

10. A bound indicator as claimed in claim 1 wherein said organic indicator is an N,N-dialkylaniline.

11. A bound indicator as claimed in claim 1 wherein said organic indicator is selected from the group consisting of diazo, amino, carboxy and alkylsilane deriVatives of N,N-dimethylaniline.

12. A bound indicator as claimed in claim 1 wherein said organic indicator is selected from the group consisting of B-naphthol and derivatives thereof.

13. A bound indicator as claimed in claim 1 wherein said organic indicator is selected from the group consisting of triarylmethyl compounds.

14. A bound indicator as claimed in claim 1 wherein said organic indicator is phenolphthalein.

15. A bound indicator as claimed in claim 1 wherein said indicator is methylene blue.

16. A bound indicator as claimed in claim 1 wherein said organic indicator is Eriochrome Black T.

17. A process for the preparation of the bound indicator of claim 1 which includes the steps of providing a silane which has an organofunctional group, causing the silane to react with a carrier which has available hydroxyl or oxide groups, and causing the organofunctional group of the silane to react with an indicator.